Manufacture of chlorohydrins



Jdn 27, 1939. H. M GUINOT 2,164,240

MANUFACTURE OF CHLOROHYDRINS File'd Feb. 26, 1936 ('ENIAIFUGE C'ENTEIFUQE H. M. Gui/10f ATTORNEY Patented June 27, 1939 l om'rso STATES MANUFACTURE OF S Henri Martin Gninot, Niort, Dons-Sevres, France, assis'nor to Usincs do Melle, Melle, France, a

corporation of Application February. 28, 1936. Serial No. 65,915 In France March 8, 1935 a cam (01. zoo-ow This invention relates to the manufacture o! ,chlorohydrinsh It is well: known to produce chlorohydrins by the action of olefin'e bYdlOOflI-a bons on aqueous solutions ot-hypochlorous acid, the latter being generally obtained by the hydrolysis of chlorine dissolved in water, in accordance with the reaction However, when this method of worldng is employed, oneis always more'or less obliged to put up with the undesirable lormation o! the corresponding dlchlorides, owing to the great aifluity of chlorine for the oleflne hydrocarbons treated.

Finally, owing to the great ease with which chlorohydrins are saponifled by the action of boiling water, it is difficult to remove them in the pure state from the aqueous solutions obtained aseiplained above without at the same time destroying a fairly large quantity of them by hydrolysis.

The present invention has for its object the provision of a process which will enable all the abovementioned dimculties'to be overcome. It consists in 'eiIecting, simultaneously, in two distinct operating regions, on the one hand the solution ot'chlorine in water and, on the other hand the action or the olefine on the solution 01 hypochlorous acid thus obtained, and in ensur ing, in each of these two operating regions, the absorption of the corresponding gas by means of a powerful agitation which is capable of causin at the same time a pressure reduction which produces a continuoi'm circulation or liquid between the two regions. In this way the employment of thegenerally previously known circulating pumps and the trouble which such employment usually involves are avoided.

Another characteristic 0! the invention resides in the method of treatment of the resultant aqueous solution of chlorohydrin with a view to freeing it from the small quantity oi' dichioride that it may contain and extractins it the chlorohydrin in a pure and anhydrous This method'of treatment consistsin first 01 all extracting'the' dichloride by means of a, small quantity of a solvent which'is only slightly solub.: in water and which has only a slight malty lor the chiorohydrin itself. For this mirliicatlon there may b'eused an extraction battery oba known type, for example, the onwhich has been descrlbed ,in French Patent Specifications Ho. 671,482 and No. 178,689. The solution ol chlorohydrln thus purified isthen treated in a second battery, which a larger number of elementsthan the first, with a large volumeoi a solvent (or a mixture 01' solvents) which posan advantageous coeflicient of extraction and is chosen so that it is possible to dehydrate the chlorohydrin easily by azeotropic distillation.

This method of treatment enables the disadvantages of the classic method tube avoided, according to which the solutions are distilled with a view to obtaining binary water-chlorohydrin mixtures, in the course of the distillation of which a fairly large quantity of chlorohydrin is lost by The accomp yi drawing represents diagrammatically, in one of its embodiments, the apparatus for the manufacture of aqueous solutions of chloro ydrins.

The apparatus comprises essentially two vessels A and B which communicate with a chlorine gasometer C and an oleflne gasometer respective-' ly and which are connected together by pipes Ta and Tb that enable the liquid to circulate between the two vessels. These two vessels, constituting two separate operating regions, are preferably made 01' stoneware and are each provided with a centrifuge that rotates at a speed that is sufllclent for the production, in the liquid,- of a vortex with a suction cone which leaves the topv face or the centrifuge uncovered, The centrifuges are denoted by E and Frespectively and their driving motors by G and K respectively. In this way, I

the gas which constitutes the atmosphere o! the vessel is sucked into the hollow cone of the vortex andiorclbly emulsified in the liquid. on the other hand, the reduction of pressure produced in the liquid in the neighbourhood of the centri-" use in one vessel enables the liquid contained in the other vessel to be drawn by,suction through the pipes To and Th. Each pipe is connected to one vessel at a position high up where the liquid rises by centrifugal action and to the other yesso] at a lower level. As these pipes are assumed beneficial because the reaction und r considerationisaceompaniedbyanevolutionoiheat. In order to start the apparatus. one of the vessels is connected with the chlorine", telcandtheotherwlththegasometernth atls' charged with the oleflne tobe treated. The centriiuges are caused to rotate and the opening of the cock R is regulated with a view to obtainin the optimum speed of circulation between the vessels A and B; an intense absorption of the two I gases and the mixing of the liquid follows with the formation of chlorohydrin observed. As the gaseous chlorine reaches a state of perfect solu-- tion only in the vessel in which the olefine is absorbed, the production of the dichloride is very small. The vessels A and B do not require to be hermetically sealed; in particular, the shaft of the centrifuge does not have to be provided with a stuiling box but only with a greased guide. because the static pressure which exists in the 1' vessel can be regulated so as to be as little difiercut as possible from the atmospheric pressure.

The production of chlorohydrin can be made continuous by adding water continuously preferably into the chlorine vessel and producing its removal by overflowing from the other vessel. The water tank is denoted by I in the drawing, and the overflow for removing the solution of chlorohydrin is denoted by J.

Under these conditions, the yields of chlorohydrin in relation to the products treated are excellent-i. e., of'the order of 90 to 95 per cent-4i care is taken not to allow the temperature to rise above to C. However, the production of a small quantity of dichloride, which is found in solution along with the chlorohydrin, cannot be avoided, and the elimination of the dichloride and the separation of the chlorohydrin in the pure state are eflected, as hereinbeiore stated, in extraction batteries of known type which, for the sake of simplicity, have not been represented in the figure.

Exmts I Manufacture o) the chlorohydrin of ethylene U ilcol The stoneware vessels A and B each have a capacity of about 200 litres. The centrifuges, made of glass or special steel which is unattackable by the hydrochloric solutions treated, revolve I at a speed'which is suilicient to ensure a rate of about 10 cubic metres -per hour for the liquid circulating between A and B. Under these conditions, 5 cubic metres of chlorine and ethylene per hour are absorbed in the two vessels respec- 80 tively. It is even possible to double this speed of absorption if the increase of production of ethylene chloride which results therefrom is not considered to be undesirable.

In normal working, the vessel A is charged with I 200 litres of water per hour, sothat there overflows into B a solution containing about 1 gramme-molecule of chlorohydrln per litre.

The solution in vessel B is acid; it is exactly neutralised by milk of lime.

GI After filtration, the liquid is treated continuously in an extraction battery of four elements (see the aforesaid French Patent No. 671,482) with a fifth of its volume of a selected petroleum smrlt' boiling between very narrow temperature as limit, for example, 105 to 110 C.

' mofchiorohydriniaonleavingfliebattery, mtirelytreefrunflreethylenechloridewhich it held in solution. This product is subsequently separated from the extracting petroleum spirit by 10 simple fractional The solution of chlorohydrin that has thus been -is treated continuously, in a second battery comprising twelve elements, with anequalvolumeotamixtureconsistingofiso- 16 propyl ether 50 per cent, and normal propyl al- Theaqueous coholiil per cent. This mixture has a coeihcient of extraction of 1.6 for the chlorohydrin at a concentration of 8 per cent, so that, after passing through the battery, the extraction of chlorohlydrein from the aqueous solution treated is com- 5 p e The exhausted aqueous solution is then freed, by slight boiling, from the small-quantity of solvents which it has dissolved and which is brought back into the circuit; as for the solution of 10 chlorohydrin in the solvent, it is distilled in a column at the base of which pure chlorohydrin is collected whilst at the top a mixture of residual water and the solvents employed is obtained, this mixture being passed to decantation in accord- 15 ance with the principles o1v azeotropic dehydration: according to these principles the refluxing to the column is ensured by the return of a sumcient fraction of the upper layer separated in the decanter, whilst the water and the mixture of solvents are withdrawn at the desired speed.

The pure chlorohydrin (B. P. 128 to 129 C.) is finally obtained with an excellent yield (92%), without taking into account the ethylene chloride (B. P. 83 to 84 C.) separated. g5

Manufacture of the chlorohydrin of propylene glycol Anormal aqueous solution of the chlorohydrin of propylene glycol is produced by working in the manner explained in the preceding example, with the sole diiierence that the gasometer which communicates with the vessel B contains propylene instead of ethylene. :15

After exact neutralisation by means of caustic soda, the resultant chlorohydrin solution is treated with a tenth of its volume of cyclohexane in a first extraction battery of any suitable type. This solvent used in such a small quantity has 40 very little eflect on the chiorohydrin itself but, on the other hand, is capable of extracting the whole of the propylene dichloride (B. P. 97.5 C.) which is then separated by distillation, the oyclohexane being continuously recovered as a first-fraction product (B. P. 80 to81 C.)

The solution of chlorohydrin, which has thus been purified, is treated in a second battery with twice its volume of pure benzene which possesses a coeflicient of extraction of 0.85 for the chloro-- hydrin of propylene glycol under these conditions of concentration Here again, the extracting agent serves to dehydrate the chlorohydrin by azeotropy on its subsequent separation by distillation. 111e, chlorohydrln'of propylene glycol (B. P. 125 to 127 C.) is obtained in the pure state at the base of the distillation column. The yield is 90 per 'cent calculated on the chlorine and propylene used 00 These examples are not limitative and it is also pointed out that, without departing from the scope of the present invention, all these operations can be carried out under a pressure that differs from the ordinary pressure, either with a 05 view to obtaining certain recoveries of heat during the distillation for example, or for the purpose of' the velocityof reaction during thefirststageofthepreparationoftheaoueous solutions of I m What I claim is: V

1. Prom for the continuous production of by the action of defines on aqueous soluflonsofchloriminwhichthechlorlnegasis dissolvedinwaterinoneregi mandtheresultant hypochlorous acid caused to react with the oleflne in a separate region, comprising essentially inter-,

connecting the separate regions to permit of intercirculation, emulsifying the liquid with the gas in both regions by means oi centrifugal agitation, utilizing the suction eflect of said agitation in each region to create intensive inter-circulation of liquid between the regions, regulating said circulation to ensure that the proportion of chlorine dissolved in unit volume of the liquid is extremely small and to realize substantially complete hydrolysis oi the absorbed chlorine to hypochlorous acid, continuously withdrawing the resultant chlorohydrin solution from the second region and eliminating from the aqueous chlorohydrin solution the small quantity of dichloride therein by extracting with the aid of a small quantity of a solvent only slightly soluble in water and having only a slight aflinity for the chlorohydrin itself.

2. Process for the continuous production of chlorohydrins by the action of oleflnes on aqueous solutions 01 chlorine in which the chlorine gas is dissolved in water in one region, and the resultant hypochlorous acid caused-to react with the olefine in a separate region, comprising essentially intertercircuiatlon, emulsifying the liquid with the gas in both regions by means of centrifugal agitation, utilising the suction eifect of said agitation in each region to create intensive inter-circulation oi liquid between the regions, regulating said circulation to ensure that the proportion of chlorine dissolved in unit volume oi the liquid is extremely small and to realize substantially complete hydrolysis oi the absorbed chlorine to hypochlorous acid. continuously withdrawing the resultant chlorohydrin solution iron the second region and eliminating Irom the aqueous chlorohydrin solu- Patent No. 2461;, al o.

connecting the separate regions to permit of in- A tion the small quantity oi dichloride therein by extraction with the aid 01 a small quantity 01' a solvent only slightly soluble in water and having only a slight a'flinity for the chlorohydrin itself, treating the dichloride-solvent body by distillation {or recovery of the solvent, and returning the latter for re-use-in the process.

3. Process for the continuous production of chlorohydrins by the action 0! oleflnes on aqueous solutions of chlorine in which the chlorine gas is dissolved in water in one region, and the resultant hypochlorous acid caused to react with the oleflne in a separate region, comprising essentially interconnecting the separate regions to permit oi inter-circulation, emulsifyingthe liquid with the gas in both regions by means of centrifugal agitation, utilizing the suction effect of said agitation in each region to create intensive inter-circulation of liquid between the regions, regulating said circulation to ensure that the proportion of chlorine dissolved in unit volume of the liquid is extremely small and to realize substantially complete hydrolysis of the absorbed chlorine to hypochlorous acid, continuously withdrawing the resultant chlorohydrin solution from the second region and eliminating from the aqueous chlorohydrin solution the small quantity of dichloride therein by extraction with the aid of a small quantity of a solvent only slightly soluble in water and having only a slight aflinity tor the chlorohydrin itself, separating the dichloride-solvent body from the purified aqueous chlorohydrins and finally extracting the chlorohydrin from its purifled aqueous solution with a solvent which is capable of dehydrating the chlorohydrin by subsequent azeotropicdistiliatlon oi the chlorohydrin-solvent extract.

HENRI MARTIN GU'DIOT.

cssrrrrcsrn 0F co ma.

June a7, 1959.

V HENRI MARTIN GUINQT.

It is hereby certified that the name of theassignee 1n the above mm-' bored patent was. erroneously desoribedand specified as "USiNES DE l'iELLE" whereas said name should have been described and specified as LES USINES D1; of Hello, France, a corporation of France, asshov'vn by the record or nassignments this office; and that the said Letters Patentshould be read with this correction therein that the same. may conform to the record or the ease in the Patent Office.-

a d sealed t s'29th day. or August, n; 19 9.

(Seal) Leslie Frazer,

Acting Commissioner of Patents.

hypochlorous acid caused to react with the oleiine in a separate region, comprising essentially inter-,

connecting the separate re us to permit of intercirculation, emulsifying the liquid with the gas in both regions by means oi centrifugal agitation, utilizing the suction eflect of said agitation in each region to create intensive inter-circulation of liquid between the regions, regulating said circuiation to ensure that the proportion of chlorine dissolved in unit volume of the liquid is extremely small and to realize substantially complete hydrolysis of the absorbed chlorine to hypochlorous acid, continuously withdrawing the resultant chlorohydrin solution from the second region and eliminating from the aqueous chlorohydrin solution the small quantity of dichloride therein by extracting with the aid oi a small quantity of a solvent only slightly soluble in water and having only a slight aflinity for the chlorohydrin itself.

2. Process for the continuous production of chlorohydrins by the action of oleflnes on aqueous solutions oi chlorine in which the chlorine gas is dissolved in water in one region, and the resultant hypochlorous acid caused-to react with the olefine in a separate region, comprising essentially intertercirculation, emulsifying the liquid with the gas in both regions by means of centrifugal agitation, utilising the suction eifect of said agitation in each region to create intensive inter-circulation oi liquid between the regions, regulating said circulation to ensure that the proportion of chlorine dissolved in unit volume 0! the liquid is extremely small and to realize substantially complete hydrolysis oi the absorbed chlorine to hypochlorous acid. continuously withdrawing the resultant chlorohydrin solution iron the second region and eliminating iron the aqueous chlorohydrin solu- Patent No. 2461;, al o.

connecting the separate regions to permit of in- A tion the small quantity of dichloride therein by extraction with the aid 01 a small quantity 01' a solvent only slightly soluble in water and having only a slight a'flinity for the chlorohydrin itself, treating the dichloride-solvent body by distillation {or recovery of the solvent, and returning the latter for re-use-ln the process.

3. Process for the continuous production of chlorohydrins by the action 0! oleflnes on aqueous solutions of chlorine in which the chlorine gas is dissolved in water in one region, and the resultant hypochlorous acid caused to react with the oleflne in a separate region, comprising essentially interconnecting the separate regions to permit oi inter-circulation, emulsifyingthe liquid with the gas in both regions by means of centrifugal agitation, utilizing the suction effect 01 said agitation in each region to create intensive inter-circulation of liquid between the regions, regulating said circulation to ensure that the proportion of chlorine dissolved in unit volume of the liquid is extremely small and to realize substantially complete hydrolysis of the absorbed chlorine to hypochlorous acid, continuously withdrawing the resultant chlorohydrin solution from the second region and eliminating from the aqueous chlorohydrin solution the small quantity of dichloride therein by extraction with the aid of a small quantity of a solvent only slightly soluble in water and having only a slight aflinity tor the chlorohydrin itself, separating the dichloride-solvent body from the purified aqueous chlorohydrins and finally extracting the chlorohydrin from its purifled aqueous solution with a solvent which is capable of dehydrating the chlorohydrin by subsequent azeotropicdistiliation oi the chlorohydrin-solvent extract.

HENRI MARTIN GU'DIOT.

CERTIFICATE OF cbss scrror.

June a7, 1959.

V HENRI MARTIN GUINQT.

It is hereby certified that the name of theassignee 1n the above mm-' bored patent was. erroneously describedand specified as "USiNES DE liELLE" whereas said name should have been described and specified as LES USINES D1; of Hello, France, a corporation of France, asshov'vn by the record or nassignments this office; and that the said Letters Patentshould be read with this correction therein that the same. may conform to the record or the ease in the Patent Office.-

ia d sealed t s'29th day. or August, n; 19 9.

(Seal) Leslie Frazer,

Acting Commissioner of Patents. 

